Sales, impacted by increasing competition, including cannibalism by Ford's own newly introduced, and more affordable Mustang, dipped to 74,972. The popular 'Tilt-Away' steering column continued, and was a Thunderbird recognized feature that was later shared on other upper-level Ford Products. Exterior trim was revised, including a new grille, Thunderbird emblem replacing the block letters on the front edge of the hood, simulated front fender vent trim, revised Thunderbird scripts now located on the rear edge of the quarter panels, and revised taillight lens trim and a single center emblem replacing the dual lens birds and block letters respectively. Several features intended for the new generation were delayed until 1965, when front disc brakes became standard equipment and sequential turn signals which flashed three bulbs in the broad, horizontal tail lights from inside to outside were added the latter had been delayed by vehicle lighting regulations in the United States. The listed retail price for the 1964 two-door hardtop coupe was US$4,486 ($42,328 in 2022 dollars ), 1965 model year saw the debut of sequential turn signals The only transmission available was the Cruise-O-Matic MX 3 speed automatic. The 1964 Thunderbird was the only model of this generation to have the word 'Thunderbird' spelled out on the front hood instead of a chrome Thunderbird emblem. Total 1964 sales were excellent at 92,465 units, up nearly fifty per cent from the previous year, but the popularity of the Sports Roadster continued to decline, with only 50 Sports Roadster sold from the factory. The revised model was initially offered as a hardtop, convertible, Sports Roadster with dealer-installed tonneau cover and wire wheels, and Landau with vinyl roof, simulated landau irons, and wood grain interior appointments. Models 1964 Thunderbird Hardtop Coupe 1965 Ford Thunderbird Hardtop 1966 Town Landau Contemporary testers felt that the Buick Riviera, Pontiac Grand Prix and Chrysler 300K were substantially more roadworthy cars, but the Thunderbird retained its leading market share. The softly sprung suspension allowed considerable body lean, wallow, and float on curves and bumps. The only remnant of the Thunderbird's former sporty image was that the standard 390-cubic-inch 300 hp (224 kW) V8 engine needed nearly 11 seconds to push the heavy T-bird to 60 mph (97 km/h). This generation of the Thunderbird was restyled in favor of a more squared-off, 'formal' look.

The fourth generation Ford Thunderbird is a large personal luxury car produced by Ford for the 1964 to 1966 model years.

Custom 66 thunderbird